1. Field of the Invention
The present invention relates to a hood retaining structure for heat-dissipating device, and more particularly to a hood retaining structure for heat-dissipating device such that a hood can be easily assembled and disassembled to the heat-dissipating device.
2. Description of Related Art
The computer system generally comprises central processing unit (CPU) on motherboard there for computation and processing. The CPU will generate considerable heat as the computation speed thereof is rapidly increased. Therefore, heat-dissipating device is provided for the CPU and conveys the heat generated by CPU to the ambient outside the computer mainframe, whereby the performance of the CPU is not degraded by high temperature.
FIG. 1 is a sectional view of a prior art heat-dissipating device 10a, which comprises a heat-dissipating block 1a made of material with fast heat dissipation and low heat conductance such as aluminum, and a heat-dissipating fin set 3a on the heat-dissipating block 1a. The heat-dissipating fin set 3a comprises a plurality of fins 31a with equal pitch therebetween. A dent 11a is defined on bottom of the heat-dissipating block 1a and a heat-conducting block 2a is arranged in the dent 11a. The heat-conducting block 2a is made of material of slow heat dissipation and high heat conductance such as aluminum. Moreover, the heat-dissipating device 10a further comprises a hood 4a and a heat-dissipating fan 5a. 
The heat-dissipating device 10a is then assembled on the CPU 20a with the heat-conducting 2a is attached to top of the CPU 20a. The high heat conductance property of the copper heat-conducting 2a fast conveys the heat generated by the CPU 20a to the heat-dissipating block 1a. The heat is then dissipated to external ambient by the excellent heat dissipation ability of the aluminum heat-dissipating block 1a and the heat-dissipating fin set 3a. Therefore, the heat-dissipating device 10a has satisfactory heat conductance and heat dissipation ability.
However, the heat-dissipating fan 5a is generally retained to the hood 4a by bolt when the hood 4a is assembled to the heat-dissipating fin set 3a. The assembling and disassembling of the heat-dissipating fan 5a is cumbersome. It is desirable to provide a retaining structure to fast assemble and disassemble the hood.